Generate leaner P4 VM

Dev: 1.5 GB instead of 3.5 GB
Tutorial: 2.3 GB instead of 5.5 GB

Change-Id: Ib63d47578a2c9e16a97827bfba463f90cfe1187d
diff --git a/tools/dev/p4vm/install-p4-tools.sh b/tools/dev/p4vm/install-p4-tools.sh
index 8625daa..a5c5bee 100755
--- a/tools/dev/p4vm/install-p4-tools.sh
+++ b/tools/dev/p4vm/install-p4-tools.sh
@@ -71,17 +71,13 @@
         mktemp \
         pkg-config \
         protobuf-c-compiler \
-        python \
-        python-dev \
-        python-ipaddr \
-        python-pip \
-        python-scapy \
-        python-setuptools \
+        python2.7 \
+        python2.7-dev \
         tcpdump \
         wget \
         unzip
 
-    sudo pip install setuptools cffi grpcio
+    sudo -H pip install setuptools cffi grpcio scapy ipaddr
 }
 
 function do_requirements_1404 {